What is the Recommended PH Level for Growing Cantaloupe?

Cantaloupes (Cucumis melo reticulous), also known as muskmelons, belong to the cucurbit family, a group that also include zucchini and pumpkins. Cantaloupes are round or oval-shaped melons that have orange flesh and a musky-sweet flavor and fragrance. The melon matures 75 to 100 days after seeding. Cultivars include "Earlisweet," a small melon that averages 2 to 3 pounds and is ready for harvesting early in the season. Other varieties include the 8-pound "Superstar" and the 3- to 4-pound "Saticoy," a late season cantaloupe. Measuring the pH of the soil in your intended planting area is important to ensure a successful harvest.

Significance of Soil pH

Soil pH measures the acidity or alkalinity of the soil using a scale of 0 to 14. Numbers less than 7 indicate acidity, numbers greater than 7 indicate alkalinity, and 7.0 is neutral. The pH of the soil directly affects the quality of the plants that you grow since it impacts the nutrients that are available to plants and the plants' capability for absorbing those nutrients. Planting cantaloupes in soil that is not within their ideal pH range can cause nutrient deficiencies and diminished or irregular fruit production.

The Ideal pH

Soil pH testing kits are widely available at local garden centers or online. This is one of the easiest ways to determine the pH of the soil in your outdoor space. Alternatively, gardeners can also submit a soil sample to their local university cooperative extension to have the pH and mineral content analyzed. According to the University of Minnesota Extension, the ideal soil pH for planting cantaloupes ranges from 6.0 to 6.5. Growing cantaloupes in soil that is too acidic or not acidic enough produces plants with yellow leaves, diminished flowering capability and less fruit.

Lowering pH

Growing cantaloupes in soil with a pH that is higher than 6.5 may cause yellowing of the leaves, a condition known as iron chlorosis. According to Clemson Cooperative Extension, gardeners can use one of two products to lower pH. Aluminum sulfate lowers the soil's pH immediately, while sulfur is more gradual. The exact amount of the pH-altering soil amendment that you need to use depends on the current pH level of your soil and the product being used. In general, you may need up to 3 pounds of aluminum sulfate for every 10 square feet of planting area or one-half pound of sulfur for every 10 square feet. Follow manufacturer recommendations for best results.

Raising Soil pH

Overly acidic soil can be equally harmful to your crops. Growing cantaloupes in soil with a pH lower than 6.0 may cause yellowed foliage and irregular fruit production. Clemson Cooperative Extension recommends raising soil pH with lime or wood ashes. Ground agricultural limestone is available in four types, including pulverized, pellets, granular and hydrated. Wood ashes are less effective than limestone but contain nutrients such as boron, phosphate and potassium. Organic options include adding compost or manure, alkaline products that will raise soil pH while also adding nutrients and enhancing soil drainage.